1. Field of the Disclosure
The present disclosure relates generally to an apparatus and method for performing a channel decoding operation based on an effective noise in a mobile communication system, and more particularly, to an apparatus and method for channel decoding based on a log likelihood ratio (LLR), which is based on an effective noise in a mobile communication system.
2. Description of the Related Art
In a wireless channel environment of a communication system, errors inevitably occur due to a number of factors such as multipath interference, shadowing, propagation attenuation, time-variant noise, interference, fading, etc. As a result of these errors, information loss occurs.
Further, this type of information loss results in distortion of a transmitted signal, degrading the overall performance of the mobile communication system.
Various error-control schemes have been proposed in order to improve the reliability of a communication by addressing the information loss. For example, a typical error-control scheme uses an error-correcting code, such as a forward error correction (FEC) code. Examples of the FEC code include a convolutional code, a turbo code, a low density parity check (LDPC) code, etc.
Additionally, various channel decoding schemes have been proposed, e.g., a channel decoding scheme based on an LLR.
Effective noise experienced by a channel decoder in a signal receiving apparatus includes noise that occurs during a channel estimating operation performed when the signal receiving apparatus performs channel decoding and additive noise that occurs in a communication channel environment between a signal transmitting apparatus and the signal receiving apparatus. Generally, the noise that occurs during the channel estimating operation is much less than the additive noise that occurs in the communication channel environment between the signal transmitting apparatus and the signal receiving apparatus. As a result, conventional channel decoding schemes address only a channel decoding operation which considers only additive noise occurring in the communication channel environment between the signal transmitting apparatus and the signal receiving apparatus. That is, the conventional channel decoding schemes do not consider the noise that occurs while a channel estimating operation is performed, thereby decreasing the reliability of the channel decoding operations.